Interpretation ID: nht68-4.1

DATE: 08/15/68

FROM: AUTHOR UNAVAILABLE; David A. Fay; NHTSA

TO: Toyota Motor Company

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of July 23, 1968, to Mr. George C. Nield, Acting Director, Motor Vehicle Safety Performance Service, concerning the requirements for turn signal and hazard warning signal flashers as specified by Motor Vehicle Safety Standard No. 108.

With certain exceptions, paragraph S3.3 of Standard No. 108 permits the use of combination lamps, reflective devices and items of associated equipment, provided the requirements for each lamp, reflective device and item of associated equipment are met. Therefore, a combination turn signal and hazard warning signal flasher may be used, provided the requirements for each signal (turn and hazard warning) are met.

You are correct in your understanding that Standard No. 108 and basically referenced SAE Standards J590 and J945 do not require operation of the flasher unit with only one signal bulb in the test circuit. The standard test circuit shown in Figure I of SAE Standard J823 indicates a minimum of two signal lamps and one pilot indicator lamp as the lamp load.

Thank you for writing.